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Late‐stage functionalization of indoles can be a valuable strategy for modifying different existing indolyl‐drugs and natural products to get their new analogues. In this study, we report the photoredox‐metal catalyzed decarboxylative arylation strategy of indole‐3‐acetic acids with aryl halides. Here, photoredox‐catalysis was synergistically merged with nickel‐catalysis for the synthesis of biologically important 3‐benzyl indoles with good functional group tolerance. The merit of this methodology is demonstrated by the synthesis of amino acid derived substrates 3 p, 3 v and 3 x. [ABSTRACT FROM AUTHOR]

Here in we report, rhodium(III)‐catalyzed decarboxylative acylation of arenes using α‐oxocarboxylic acids as acyl surrogate. In this strategy, O–NHAc group act as an autocleavable oxidizing directing group (ODGauto), thus giving rise to ortho‐acylated phenols in moderate to good yields. Mechanistic studies provided strong support for a kinetically relevant C–H bond activation. According to the best of our knowledge, this is the first report of Rhodium catalyzed decarboxylative acylation. [ABSTRACT FROM AUTHOR]

A Rh(III)-catalyzed regioselective redox-neutral cascade process of carbenoid functionalization followed by dephosphonylative annulation of benzoic acids with α-diazo-β-keto phosphonate has been realized, which led to the direct synthesis of a privileged 3-substituted isocoumarin scaffold. To the best of our knowledge, this is the first report of a complete redox neutral method to synthesize isocoumarins using C-H functionalization strategy. In the catalytic cycle of this reaction, there are two possible pathways for the C-C coupling between ortho-positioned carbon atom of benzoic acid and the diazo carbon atom: (i) concerted 1,2-aryl shift and (ii) stepwise metal-carbene formation followed by migratory insertion. DFT study has predicted that the concerted pathway has lower activation energy as compared to the stepwise pathway by 1.5 kcal/mol.

A modular strategy to obtain three different products from a single substrate was developed. The present methodology unveils new step-economical and cost-efficient routes to access diverse fused quinazolinoquinazolinone derivatives which are not prevalent in literature. Owing to the importance of quinazolinones in therapeutics, quick access to the arena of these scaffolds could be a valuable addition to the scientific domain of heterocyclic chemistry.